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Phase function defined

Vn is often called the barrier of rotation. This is intuitive but misleading, because the exact energetic barrier of a particular rotation is the sum of all V components and other non-bonding interactions with the atoms under consideration. The multiplicity n gives the number of minima of the function during a 360° rotation of the dihedral angle o). The phase y defines the exact position of the minima. [Pg.343]

Many successful projects have shown that application information can be divided into the following four categories Terminology, Special Characteristics, Abstract Functions, and Graphics. Although these categories are the basis for the searchable application data base, each project requires a conceptual phase to define how to focus. [Pg.606]

For smectic phases the defining characteristic is their layer structure with its one dimensional translational order parallel to the layer normal. At the single molecule level this order is completely defined by the singlet translational distribution function, p(z), which gives the probability of finding a molecule with its centre of mass at a distance, z, from the centre of one of the layers irrespective of its orientation [19]. Just as we have seen for the orientational order it is more convenient to characterise the translational order in terms of translational order parameters t which are the averages of the Chebychev polynomials, T (cos 2nzld)-, for example... [Pg.74]

A partial differential equation is then developed for the number density of particles in the phase space (analogous to the classical Liouville equation that expresses the conservation of probability in the phase space of a mechanical system) (32>. In other words, if the particle states (i.e. points in the particle phase space) are regarded at any moment as a continuum filling a suitable portion of the phase space, flowing with a velocity field specified by the function u , then one may ask for the density of this fluid streaming through the phase space, i.e. the number density function n(z,t) of particles in the phase space defined as the number of particles in the system at time t with phase coordinates in the range z (dz/2). [Pg.235]

The relationship between temperature sensitivity and burning rate is shown in Fig. 7.21 as a function of AP particle size and burning rate catalyst (BEFP).li31 The temperature sensitivity decreases when the burning rate is increased, either by the addition of fine AP particles or by the addition of BEFP. The results of the temperature sensitivity analysis shown in Fig. 7.22 indicate that the temperature sensitivity of the condensed phase, W, defined in Eq. (3.80), is higher than that of the gas phase, 5), defined in Eq. (3.79). In addition, 4> becomes very small when the propel-... [Pg.193]

Ultrafast laser excitation gives excited systems prepared coherently, as a coherent superposition of states. The state wave function (aprobabihty wave) is a coherent sum of matter wave functions for each molecule excited. The exponential terms in the relevant time-dependent equation, the phase factors, define phase relationships between constituent wave functions in the summation. [Pg.905]

We have chosen to call the two phases resin and fiber. Each phase will be denoted by subscript r and respectively. A similar phase function (i.e., Yf) can be defined for the fiber phase. It should be noted that if the fiber phase is stationary Y is not a function of time. [Pg.160]

The computer-reconstructed catalyst is represented by a discrete volume phase function in the form of 3D matrix containing information about the phase in each volume element. Another 3D matrix defines the distribution of active catalytic sites. Macroporosity, sizes of supporting articles and the correlation function describing the macropore size distribution are evaluated from the SEM images of porous catalyst (Koci et al., 2006 Kosek et al., 2005). Spatially 3D reaction-diffusion system with low concentrations of reactants and products can be described by mass balances in the form of the following partial differential equations (Koci et al., 2006, 2007a). For gaseous components ... [Pg.121]

While writing the above expression, the facts that have been used are GsD = CSC, GsBD = CqC0, and (G ) 1 = (CsylC l. Note that the definition of GsBD is different from the previous formulation [9] this follows from the difference in definition of CB, which has been discussed before. Here Cs and C are the phase space correlation functions defined as... [Pg.102]

The second equation poses no problem because 8 was defined as a phase function. If T) < 1, the solution for S is trivial, as the standard field with form. st then becomes a knot. The same happens if q is bounded, say, if q <4, because we can then take as the Clebsch variables q = q/ , 8 = n 8, where n is an integer greater than A. Dropping the primes and entering the new Clebsch variables in (144), it is clear that there then exists a solution for S, y. [Pg.237]

The final choice to be made is the form of the order parameter in this case the default (built out of the energy function) defined in Eq. (53) proves the right choice. Thus, making the phase labels explicit we take... [Pg.35]

Example B hep and fee Phases of Hard Spheres. We have already noted that the order parameter in ESPS need not be constructed out of the true energy functions of the two phases. The defining characteristic of an ESPS order parameter is that it measures the difference between the values of some chosen function of the common coordinate set u evaluated in the two phases, such that for some region (typically sufficiently small values ) of that quantity, an interphase switch can be successfully initiated. An ESPS order parameter merely provides a convenient thread that can be followed to the wormhole ends. [Pg.35]

In both cases the species, forms or phases are defined (a) functionally, (b) operationally, or (c) as specific chemical compounds or oxidation states. This usage is employed in this book but IUPAC has proposed a useful clarification in that definition (1) above is abandoned in favour of speciation analysis and the term spe-ciation is reserved for the concept of a description of the distribution of species. [Pg.4]

The directional distribution of the scattering intensity can be described by phase functions. A phase function is defined as the ratio of scattering intensity in a direction to the scattering intensity in the same direction if the scattering is isotropic. Thus, it is a normalized function and is defined over all directions. Typical phase functions for small, intermediate, and large values of f and n, are illustrated in Fig. 4.4, with the spheres assumed to be nonabsorbing [Tien and Drolen, 1987]. It is shown that the phase functions mainly vary... [Pg.145]

The set of stochastic equations given by (3.37) is equivalent (in the linear case) to equations (3.11) with the memory functions defined in Section 3.3, but, in contrast to equations (3.11), set (3.37) is written as a set of Markov stochastic equations. This enables us to determine the variables that describe the collective motion of the set of macromolecules. In this particular approximation, the interaction between neighbouring macromolecules ensures that the phase variables of the elementary motion are co-ordinates, velocities, and some other vector variables - the extra forces. This set of phase variables describes the dynamics of the entire set of entangled macromolecules. Note that the Markovian representation of the equation of macromolecular dynamics cannot be made for any arbitrary case, but only for some simple approximations of the memory functions. We are considering the case with a single relaxation time, but generalisation for a case with a few relaxation times is possible. [Pg.56]

More widely applied to determine the potential, plant and human bioavailability are the methods of PTMs speciation which involve selective chemical extraction techniques. Estimation of the plant- or human-available element content of soil using single chemical extractants is an example of functionally defined speciation, in which the function is plant or human availability. In operationally defined speciation, single extractants are classified according to their ability to release elements from specific soil phases. Selective sequential extraction procedures are examples of operational speciation (Ure and Davidson, 2002). [Pg.179]

The envelope function defines the pulse repetition time T = 27r/u>r by demanding A(t) = A(t — T). Inside the laser cavity the difference between the group velocity and the phase velocity shifts the carrier with respect to the envelope after each round trip. The electric field is therefore in general not periodic with T. To obtain the spectrum of E(t) the Fourier integral has to be calculated ... [Pg.127]

It is appropriate to consider gastrointestinal structure in relation to gastrointestinal function. The function of the digestive system is to break down complex molecules, derived from ingested food, into simple ones for absorption into the blood or the lymph. This process occurs in five main phases, within defined regions of... [Pg.132]

Usually, a number of ions N is very large, and description of the system on the basis of this probability density is very inconvenient. Often, it is enough to restrict the consideration to lower order phase-space distribution functions defined as... [Pg.451]

In the general case, the spatial distribution of the phases can be formally represented by the so-called phase function ft IR3 —s- 0 1 for each phase /. The phase function is defined as (Adler, 1992, 1994)... [Pg.140]


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See also in sourсe #XX -- [ Pg.72 , Pg.384 ]




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